Cancer stem cells and epithelial-to-mesenchymal transition in lung cancer

Longkanker is een veel voorkomende ziekte met vaak een slechte prognose. Dit komt met name doordat de ziekte meestal in een vergevorderd, uitgezaaid stadium ontdekt wordt. De kankerstamcel theorie zegt dat de kankerstamcellen (CSC), een klein percentage van de tumorcellen, verantwoordelijk is voor uitgezaaide ziekte (metastases) en resistentie voor behandeling. Ook wordt verondersteld dat een differentiatie proces, epitheliale naar mesenchymale transitie (EMT) genoemd, bijdraagt tot een aggresiever karakter van tumorcellen en verspreiding ervan door het lichaam via de bloedbaan. Tumorcellen in de bloedbaan worden circulerende tumorcellen (CTC) genoemd. In dit proefschrift hebben we bovenstaande theorie en processen onderzocht bij kleincellig longkanker, met name in relatie tot uitgezaaide ziekte en resistentie voor behandeling. We vonden geen verschillen in EMT eigenschappen, maar wel een toename van CSC eigenschappen tijdens ziekteprogressie in een celkweekmodel. In een eerdere studie bleken hoge aantallen CTC in het bloed voorspellend te zijn voor de reactie op chemotherapie en overlevingsduur van patiënten. Vervolg onderzoek in deze patiëntengroep liet geen duidelijke correlatie zien tussen CSC en EMT kenmerken in de tumor en het aantal CTC in het bloed van patiënten. Wel leken tumoren met verhoogde mesenchymale kenmerken samen te hangen met een betere prognose, wat enigszins verrassend is aangezien de theorie het tegenovergestelde voorspeld. Ten slotte, in een niet-kleincellig celkweekmodel bezaten mesenchymale cellen verhoogde chemoresistentie, invasief gedrag en CSC eigenschappen ten opzichte van epitheliale cellen. Concluderend, de bijdrage van CSC en EMT bij longkanker is niet eenduidig in deze studies en dient nader uitgezocht te worden

A study of drug utilization in indoor patients of high-risk pregnancy in a tertiary care hospital

Background: High-risk pregnancy is an important determinant of drug use during pregnancy. The aim of study was to evaluate drug use pattern according to WHO core-drug prescribing indicators and US-FDA pregnancy category in indoor patients of high-risk pregnancy.Methods: It was a prospective, observational study. All high-risk pregnant women admitted to tertiary care hospital and willing to give consent were included. The data was collected from 290 patients over 12 months. The data was analysed to evaluate drug utilization according to WHO core drug use indicators and in relation to US-FDA pregnancy risk category.Results: The study found that 74.82% of women were between 20-30 years of age and were admitted during third trimester of pregnancy. The most commonly prescribed drug class was vitamins and minerals prescribed in 82.75% patients. Average number of drugs per encounter was 6.4. Percentage of drugs prescribed by generic name and from essential drug list was 73.07% and 77.07% respectively. Percentage of encounters with an antibiotic and an injection prescribed was 29.31% and 65.17% respectively. The prescription of drugs belonging to US-FDA pregnancy drug categories A, B and C were 92.06%, 86.55% and 4.82% respectively.Conclusions: Overall, the principles of rational prescribing were followed according to the various drug use indicators mentioned by the WHO and US FDA pregnancy risk category. Further studies are required to find out specific drug or drug therapy related problems and plan targeted interventions to improve drug use

Biofunctionalized Capillary Flow Channel Platform Integrated with 3D Nanostructured Matrix to Capture Circulating Tumor Cells

Circulating tumor cells (CTCs) from peripheral blood account genetic information for cancer diagnosis and overall disease monitoring. Analysis of “liquid biopsy” holds immense promise as it may lead to new approaches for cancer treatment. The study reports effective and continuous flow microchannel system for isolating CTCs using transferrin conjugated 3D matrix synthesized by crosslinking polyethylene glycol-Fe3O4 nanostructures for rapid and efficient capturing of CTCs. The platform provides option of using multiple microchannel units in series that can influence higher cell-capture efficiency due to increasing cell-substrate contact frequency. CTCs are captured with high efficiency even at low concentration of target cells (~90% at 25 cells per mL blood). Furthermore, the study demonstrates that the cell-capture performance is influenced by topographic interactions between nanostructure based matrix and cancer cells of interest. In addition, this study demonstrates the “proof of concept” using 3D microchannel system having capacity of simultaneously capturing and permanently eliminating CTCs from peripheral blood samples. Further, the study evaluates clinical samples of colon and breast cancer patients for rapid isolation of CTCs. Conclusively, the present platform demonstrates inordinate capacity for cancer cell sorting, biological studies of CTCs, and cancer metastasis, potentially benefiting the real time liquid biopsy and early prognosis of cancer

A unique small cell lung carcinoma disease progression model shows progressive accumulation of cancer stem cell properties and CD44 as a potential diagnostic marker

OBJECTIVES: Cancer stem cells (CSCs) have been implicated in disease progression of aggressive cancers including small cell lung carcinoma (SCLC). Here, we have examined the possible contribution of CSCs to SCLC progression and aggressiveness. MATERIALS AND METHODS: GLC-14, GLC-16 and GLC-19 SCLC cell lines derived from one patient, representing increasing progressive stages of disease were used. CSC marker expressions was determined by RT-qPCR and western blotting analyses, and heterogeneity was studied by CSC marker expression by immunofluorescence microscopy and flow cytometry. Colony formation assays were used to assess stem cell properties and therapy sensitivity. RESULTS: Increasing expression of stem cell markers MYC, SOX2 and particularly CD44 were found in association with advancing disease. Single and overlapping expression of these markers indicated the presence of different CSC populations. The accumulation of more homogeneous double- and triple-positive CSC populations evolved with disease progression. Functional characterization of CSC properties affirmed higher proficiency of colony forming ability and increased resistance to γ-irradiation in GLC-16 and GLC-19 compared to GLC-14. GLC-19 colony formation was significantly inhibited by a human anti-CD44 antibody. CONCLUSION: The progressive increase of MYC, SOX2 and particularly CD44 expression that was accompanied with enhanced colony forming capacity and resistance in the in vitro GLC disease progression model, supports the potential clinical relevance of CSC populations in malignancy and disease relapse of SCLC

Serum-Induced Differentiation of Glioblastoma Neurospheres Leads to Enhanced Migration/Invasion Capacity That Is Associated with Increased MMP9

Glioblastoma (GBM) is a highly infiltrative brain tumor in which cells with properties of stem cells, called glioblastoma stem cells (GSCs), have been identified. In general, the dominant view is that GSCs are responsible for the initiation, progression, invasion and recurrence of this tumor. In this study, we addressed the question whether the differentiation status of GBM cells is associated with their invasive capacity. For this, several primary GBM cell lines were used, cultured either as neurospheres known to enrich for GSCs or in medium supplemented with 10% FCS that promotes differentiation. The differentiation state of the cells was confirmed by determining the expression of stem cell and differentiation markers. The migration/invasion potential of these cells was tested using in vitro assays and intracranial mouse models. Interestingly, we found that serum-induced differentiation enhanced the invasive potential of GBM cells, which was associated with enhanced MMP9 expression. Chemical inhibition of MMP9 significantly reduced the invasive potential of differentiated cells in vitro. Furthermore, the serum-differentiated cells could revert back to an undifferentiated/stem cell state that were able to form neurospheres, although with a reduced efficiency as compared to non-differentiated counterparts. We propose a model in which activation of the differentiation program in GBM cells enhances their infiltrative potential and that depending on microenvironmental cues a significant portion of these cells are able to revert back to an undifferentiated state with enhanced tumorigenic potential. Thus, effective therapy should target both GSCs and differentiated offspring and targeting of differentiation-associated pathways may offer therapeutic opportunities to reduce invasive growth of GBM

Targeting apoptosis pathways in lung cancer

<p>Lung cancer is a devastating disease with a poor prognosis. Non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) represent different forms of lung cancer that are associated with distinct genetic causes and display different responses to therapy in the clinic. Whereas SCLC is often sensitive to chemotherapy at start of treatment, NSCLC are less chemo-sensitive. In NSCLC different histological subtypes are distinguished and increasing efforts are made to identify subtypes that respond to specific therapies, such as those harbouring epidermal growth factor receptor (EGFR) mutations that have benefit from treatment with EGFR inhibitors. Targeting of the apoptotic machinery represents another approach that aims to selectively kill cancer cells while sparing normal ones. Here we describe different ways that are currently explored to induce apoptosis in lung cancer cells, specifically pathways controlled by TNF-related apoptosis-inducing ligand (TRAIL), BCL-2 family members and apoptosis inhibitory proteins (IAPs). Preclinical studies are discussed and for some agents results from early clinical studies and future perspectives are considered. (C) 2010 Elsevier Ireland Ltd. All rights reserved.</p>

Buffalopox outbreak in humans and animals in Western Maharashtra, India

An outbreak of febrile illness with rash was reported in humans and buffaloes with pox lesions in some villages of Solapur and Kolhapur districts of Maharashtra state, India. Detailed clinico-epidemiological investigations were done with collection of blood, vesicular fluid and scab from humans and animals. A total of 166 suspected human cases from Kasegaon village in Solapur district and 185 cases were reported from 21 different villages from Kolhapur district. The attack rate in humans in Kasegaon village was 6.6% while in Kolhapur district the attack rate for buffaloes was 11.7%. Pox-like lesions were associated with fever, malaise, pain at site of lesion and axillary and inguinal lymphadenopathy in the humans. Infected buffaloes had lesions on teats, udders, external ears and eyelids. Laboratory investigations included detection of Buffalopox virus (BPXV) by electron microscopy (EM), virus isolation and polymerase chain reaction (PCR). Presence of BPXV was confirmed in 7 human cases and one buffalo in Kasegaon and 14 human cases from Kolhapur. The virus was isolated from 3 clinical specimens and Orthopoxvirus (OPXV) particles could be observed in EM. Thus, BPXV was identified as the etiological agent of the outbreak among both humans and buffaloes. Phylogenetic analysis based on the ATI and C18L gene revealed that a single strain of virus is circulating in India. Re-emergence of OPXV like BPXV is a real danger and contingency planning is needed to define prophylactic and therapeutic strategies to prevent or stop an epidemic. Considering the productivity losses caused by buffalopox infection and its zoonotic impact, the importance of control measures in reducing the economic and public health impact cannot be underestimated

Serum-differentiated GBM cells show enhanced infiltration in vivo.

<p><b>a.</b> Immunohistochemical staining with Nestin on xenografts derived from differentiated (GG16D) and undifferentiated (GG16 Nsp) at day 7 and day 21 post intracranial injection; overview (magnification x5) and enlarged picture (magnification x20) are being shown. <b>b.</b> Mann-Whitney U tests showing significant differences in the number of infiltrating cells between implanted neurosphere and differentiated cells, both at 7 days (p = 0,001) and 21 days (p = 0,004). The average number of infiltrating cells per section and standard deviations are indicated. <b>c.</b> Immunohistochemical staining with GFAP.</p

Model depicting the proposed effect of differentiation on GBM progression.

<p><b>a.</b> Differentiation enhances the migration and invasive potential of GBM cells. The differentiated cells can (partially) revert back to an undifferentiated/ stem cell state involving signals derived from the microenvironment. <b>b.</b> During GBM progression differentiated cells emanating from the primary tumor have enhanced infiltrative capacity and penetrate deeper in to the normal brain parenchyma. The early differentiated cells can revert back to an undifferentiated/stem cell state with unlimited proliferative potential and produce a secondary lesion away from the primary tumor. Alternatively an additional possibility is that the more invasive differentiated GBM cells pave the way for GSCs by generating a passage and suitable conditions for GSCs to follow their track.</p